DTC C1A6A Infrared Signal Circuit: Description

WARNING: This page is about a different car, the 2008 Lexus LS 600hL. However, it is still accessible from the selected car via links, so may be relevant.

The driving support ECU uses the front millimeter wave radar sensor, driver monitor camera and object recognition camera to detect obstacles in front of and behind the vehicle, and detect the direction that the driver's head is facing Based on this information, the driving support ECU sends pre-collision control operation signals.

The headlight's hi beam part is equipped with a near infrared ray filter. While driving at night, when the light conditions surrounding the vehicle are the darker than a certain threshold, the headlights are automatically changed to hi beam mode, and the near infrared ray filter is activated. By emitting near infrared rays toward the area in front of the vehicle, the object recognition camera's ability to detect obstacles is improved.

HINT:

Even if hi beam mode is automatically set, occupants in oncoming vehicles will not be affected as the near infrared filter is activated.

When there is a malfunction in the wire harness between the object recognition ECU and headlight, and a headlight (Lo beam) malfunction signal is received, this DTC is output.

This DTC is also output from the dynamic radar cruise control system.

DTC TROUBLE DETECTION CONDITION CHART

DTC Code	DTC Detection Condition	Trouble Area
C1A6A	While power switch is ON (IG), if one of following conditions is detected by driving support ECU for 1 sec Headlight (lo beam) has open circuit Near infrared ray filter position information malfunction signal is received Wire harness between object recognition ECU and headlight has open circuit Wire harness between object recognition ECU and headlight has short circuit	Headlight (Lo beam) Headlight (Near infrared ray filter) Harness or connector Object recognition ECU Driving support ECU